Neither side has faced this tall of an order this season. Here’s the breakdown.

1. Niners inside ‘backers on Saints starsNaVorro Bowman and Patrick Willis are the reason San Francisco had the league’s best all-around defense in 2011. Both are smart, supremely athletic and adept in traffic and space. Thus, both can play run or pass at the highest of levels, which is why neither comes off the field much.

All season long, defenses have tried to figure out not just how to stop Jimmy Graham and Darren Sproles, but how to simply line up against them. Do you use safeties on Graham and linebackers on Sproles? Vice Versa? Do you go with cornerbacks for both and risk getting run on?

The Niners might be the first team that doesn’t have to worry about personnel packages against these two, as they may put one First Team All-Pro linebacker on Graham and the other First Team All-Pro linebacker on Sproles. Whether the Niners can win those matchups is another discussion, but defensive coordinator Vic Fangio is extremely fortunate to be able to even consider it.

Instead of having his players focus on new strategies, he can have them focus on execution.

2. Handling the rest of New Orleans’ passing attackThe 49ers generally play zone out of their base defense and man when they go nickel or dime. Because Graham is like a third wide receiver, the Saints can stay predominantly in their base personnel if they’re more comfortable facing zone coverage. That should be the case Saturday, as San Fran’s cornerbacking trio of Tarell Brown and Chris Culliver outside and Carlos Rogers inside has been tremendous in man-to-man.

Whitner is somewhat limited in coverage (his success tends to come when linebackers are blitzing, which defines the routes quickly and makes them easier to jump). Goldson, on the other hand, is very rangy.

Both players must be careful not to overreact to the subtle fakes and body language of Drew Brees. No quarterback manipulates deep safeties better than the new single season passing yards record holder.

Pressuring Brees is critical to stopping New Orleans. (Getty Images)

3. Pressuring BreesSan Francisco is willing to blitz but often doesn’t have to, thanks to the speed of edge-rushers Aldon Smith and Ahmad Brooks. Smith works extremely well with All-Pro defensive end/tackle Justin Smith on the left side when it comes to twists and stunts. That’s something the Saints left offensive line has struggled with over the years.

This season, however, athletic left tackle Jermon Bushrod has finally polished his pass-blocking mechanics and perennial Pro Bowl guard Carl Nicks has ironed out the kinks he had in lateral pass-blocking movement. Nicks is also great at picking up Bushrod’s slack as a help-blocker.

The real key will be whether the right side of the Saints’ line can keep Brees clean. This Saints started clicking after their loss to the Rams, when Sean Payton tweaked the protections to give his tackles help with chip blocks from backs and tight ends. That’s the only way the Saints could survive the slow feet of right tackle Zach Strief.

If Ahmad Brooks draws even one true solo matchup against Strief on third-and-long, it means something has gone terribly wrong. (Or, it means the Niners will have gambled with an overload pass-rush on that side, which is plausible given that Bowman and Willis are both excellent blitzers.)

4. Niners run game against Saints DThe Niners make no bones about it: they’re going to win with Frank Gore, not Alex Smith. They’re a power-run offense – literally. Most of their offense derives from power plays, with left guard Mike Iupati pulling and fullback Bruce Miller or H-back Delanie Walker lead-blocking. The Saints have the personnel to stop this.

Former Niners tackle Aubrayo Franklin is a clogger inside and, when he shows up, veteran Shaun Rogers is a destroyer off the bench behind the generally incognito Sedrick Ellis. Also, defensive ends Will Smith and Cameron Jordan might not have dazzling sack numbers (Jordan, this year’s first round pick, recorded all of one), but both are superb at crashing inside or sliding down the line of scrimmage.

At the second level, Jonathan Vilma is regarded as the star (and rightfully so – he calls the signals and patrols sideline-to-sideline), but strong safety Roman Harper might be the deciding character on Saturday. Harper’s presence is what makes the Saints’ front seven so fast.

That will be especially important when backup running back Kendall Hunter, an underrated tempo-changer with better quickness and burst than Frank Gore, is in the game.

5. Niners big pass plays vs. Saints secondaryJim Harbaugh is masterful at installing simple wrinkles in his offense each week that take advantage of the opponent’s greatest weakness. This week that means building a few downfield shot-plays into the passing game.

The Saints led the league in 40-plus-yard pass plays allowed during the regular season. The Niners know that if they keep extra blockers in for pass protection help (which their O-line needs, especially at tackle, where Joe Staley is very average on the left side and Anthony Davis, despite getting an embarrassingly nonsensical All-Pro vote, is very inconsistent on the right side), the Saints, with their green-dog heavy blitz packages, will bring the house:

In case you missed it, in last Saturday night’s broadcast, Cris Collinsworth did a great job explaining a green dog blitz. A green-dog blitz is when a defender in man coverage rushes the quarterback after he sees that his man has stayed in to block. Thanks to the speed and aggression of their linebackers, the Saints green-dog blitz as effectively as any team in football.

Thus, there are one-on-one matchups to be had downfield. Though San Francisco’s offense has been Gingrich-level conservative this season, downfield shots off play-action, particularly when the ball’s just inside midfield, have actually been a consistent element in their gameplans.

The Niners have to intentionally design their big plays because, other than maybe tight end Vernon Davis, they don’t have anyone who can conjure them naturally.

Michael Crabtree has great body control but “inexplosive” speed. Kyle Williams is quick out of the slot but not over the top. Ted Ginn has playmaking POTENTIAL but isn’t consistent enough to be considered an actual PLAYMAKER.

Film Room: 49ers vs. Saints divisional preview

Harper's absense will have more of an effect on the run defense than the pass defense.

Since: Jan 12, 2012

Posted on: January 12, 2012 8:59 am

Film Room: 49ers vs. Saints divisional preview

I love it. It appears to be a press release for the 49ers.Their ONLY chance is if they win the turnover differntial BIG.If the Saints get a lead, and Brees can play action pass offo of run fakes, he will pick the 49ers apart. also, if the Saints geta lead, Smith willNOT be able to throw his way back intot he game.There are two scenarios here...a Saints blowout, or the Niners squeakingout a victory.And all the talk about playing outside and on grass..... will play right into Sean Payton's hands.

Since: Jul 28, 2011

Posted on: January 11, 2012 11:15 pm

Film Room: 49ers vs. Saints divisional preview

Why is this entire article dedicated to how the 49ers defense can beat the Saints? Why not write up something about how Alex Smith (billed as one of the NFC's "elite" in another article) can beat the Saints defense? I mean he is elite right?

Since: Dec 12, 2006

Posted on: January 11, 2012 5:16 pm

Film Room: 49ers vs. Saints divisional preview

Patrick Hunter? Who the hell is Patrick Hunter? I know a Kendell Hunter who is a back-up running back for the Niners and graduated from Okalahoma State after leading the Big 12 in rushing last year? Might this be the guy they are talking about? I'm pretty sure that whoever wrote this would NEVER screw up the running backs of the Saints. Dissed once again....

Since: Jan 11, 2012

Posted on: January 11, 2012 4:41 pm

great write up, as always

Good to see the 49ers getting some love on this blog. About the 49ers zone defense -- I wonder if Vic Fangio will even attempt to go to the 49ers' base 3-4 package. Given Drew Brees' ability to read blitzes and dissect zone coverages, what advantage would the 49ers gain by having two OLBs on the field? Graham can beat Parys Haralson and Ahmad Brooks in coverage, and if they drop into short zones, Brees will pick them apart. My guess is that we'll be seeing a lot more of Aldon Smith and 49ers' nickel CB Chris Culliver, while Haralson and the 49ers' gap-stuffing NT Isaac Sopoaga sit on the bench.

My question: With Roman Harper potentially missing this game with an ankle injury, how will the saints compensate? Does his absence have more of an effect on the saints' pass defense or on their run defense?

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